1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17
18package android.filterpacks.numeric;
19
20import android.filterfw.core.Filter;
21import android.filterfw.core.FilterContext;
22import android.filterfw.core.Frame;
23import android.filterfw.core.FrameFormat;
24import android.filterfw.core.GenerateFieldPort;
25import android.filterfw.format.ObjectFormat;
26
27import java.lang.Math;
28
29/**
30 * @hide
31 */
32public class SinWaveFilter extends Filter {
33
34    @GenerateFieldPort(name = "stepSize", hasDefault = true)
35    private float mStepSize = 0.05f;
36
37    private float mValue = 0.0f;
38
39    private FrameFormat mOutputFormat;
40
41    public SinWaveFilter(String name) {
42        super(name);
43    }
44
45    @Override
46    public void setupPorts() {
47        mOutputFormat = ObjectFormat.fromClass(Float.class, FrameFormat.TARGET_SIMPLE);
48        addOutputPort("value", mOutputFormat);
49    }
50
51    @Override
52    public void open(FilterContext env) {
53        mValue = 0.0f;
54    }
55
56    @Override
57    public void process(FilterContext env) {
58        Frame output = env.getFrameManager().newFrame(mOutputFormat);
59        output.setObjectValue(((float)Math.sin(mValue) + 1.0f) / 2.0f);
60        pushOutput("value", output);
61        mValue += mStepSize;
62        output.release();
63    }
64
65
66}
67